MonoMath CBSE
CBSE Maths › Class 12 PYQs › 2025

CBSE Class 12 Maths 2025 Question Paper 65/6/3 with Solutions

All 45 questions from the CBSE Class 12 Mathematics board paper, Set 65/6/3 (2025), with answers and step-by-step solutions. Total 80 marks. Tap “Show answer & solution” under any question.

Set 65/1/1Set 65/1/2Set 65/1/3Set 65/2/1Set 65/2/2Set 65/2/3Set 65/4/1Set 65/4/2Set 65/4/3Set 65/5/1Set 65/5/2Set 65/5/3Set 65/6/1Set 65/6/2Set 65/6/3Set 65/7/1Set 65/7/2Set 65/7/3

If , where ‘a’ is a constant, then is :

  1. (A)
  2. (B)
  3. (C)
  4. (D)
Show answer & solution
Answer: (A)
  1. , a constant.
  2. Differentiating: .
  3. So .
Also asked in: 2025 65/6/1, 2025 65/6/2
Q21 markMCQMatrices

If , then A is a :

  1. (A)skew-symmetric matrix
  2. (B)scalar matrix
  3. (C)diagonal matrix
  4. (D)square matrix
Show answer & solution
Answer: (D) square matrix
  1. A has 3 rows and 3 columns, so it is a square matrix.
  2. It is not skew-symmetric: the diagonal entry (and ).
  3. It is not diagonal (or scalar) because and are non-zero.

The graph shown below depicts :

Diagram for CBSE 2025 Class 12 Maths question 3
  1. (A)
  2. (B)
  3. (C)
  4. (D)
Show answer & solution
Answer: (A)
  1. The curves exist only for and , and every vertical line meets the graph in more than one point, so it is not a graph of sec x or cosec x as a function of x.
  2. The right branch passes through and approaches ; the left branch passes through between and .
  3. These are points of (, , asymptotes where ).
  4. So the graph shows (cosec⁻¹x would pass through ).

is equal to :

  1. (A)
  2. (B)
  3. (C)
  4. (D)
Show answer & solution
Answer: (D)
  1. .
  2. .
  3. Difference .
Also asked in: 2025 65/6/1, 2025 65/6/2
Q51 markMCQMatrices

Let both and be defined for matrices A and B. If order of A is , then the order of B is :

  1. (A)
  2. (B)
  3. (C)
  4. (D)
Show answer & solution
Answer: (B)
  1. Let B be of order , so is of order .
  2. is defined, so the number of columns of A equals the number of rows of : .
  3. is defined, so the number of columns of equals the number of rows of A: .
  4. So B is of order .
Also asked in: 2025 65/6/1, 2025 65/6/2
Q61 markMCQMatrices

Sum of two skew-symmetric matrices of same order is always a/an :

  1. (A)skew-symmetric matrix
  2. (B)symmetric matrix
  3. (C)null matrix
  4. (D)identity matrix
Show answer & solution
Answer: (A) skew-symmetric matrix
  1. Let and .
  2. Then .
  3. So is skew-symmetric.
Also asked in: 2025 65/6/1, 2025 65/6/2

If , then is :

  1. (A)
  2. (B)y
  3. (C)
  4. (D)
Show answer & solution
Answer: (C)
  1. , so .
  2. Differentiating again: .
  3. Multiplying by x: .
Also asked in: 2025 65/6/1, 2025 65/6/2

If is continuous at , then the value of k is :

  1. (A)a
  2. (B)
  3. (C)
  4. (D)b
Show answer & solution
Answer: (C)
  1. For continuity at 0, .
  2. and .
  3. So .
Also asked in: 2025 65/6/1, 2025 65/6/2

has a critical point at :

  1. (A)
  2. (B)
  3. (C)
  4. (D)
Show answer & solution
Answer: (B)
  1. , so and .
  2. , so gives , i.e. .

The solution for the differential equation is :

  1. (A)
  2. (B)
  3. (C)
  4. (D)
Show answer & solution
Answer: (D)
  1. , so .
  2. Integrating: .
  3. Multiplying by : , i.e. .
Also asked in: 2025 65/6/1, 2025 65/6/2
Q111 markMCQLinear Programming

For a Linear Programming Problem (LPP), the given objective function is . The feasible region PQRS determined by the set of constraints is shown as a shaded region in the graph.
(Note : The figure is not to scale)
, , ,
Which of the following statements is correct ?

Diagram for CBSE 2025 Class 12 Maths question 11
  1. (A)Z is minimum at
  2. (B)Z is maximum at
  3. (C)(Value of Z at P) (Value of Z at Q)
  4. (D)(Value of Z at Q) (Value of Z at R)
Show answer & solution
Answer: (A) Z is minimum at
  1. Z at P .
  2. Z at Q .
  3. Z at R .
  4. Z at S .
  5. The region is bounded, so Z is minimum at S and maximum at Q.
  6. (C) and (D) are false since Z at Q (9) is the largest value. So (A) is correct.
Also asked in: 2025 65/6/1, 2025 65/6/2

The order and degree of the differential equation are, respectively :

  1. (A)2, 2
  2. (B)2, not defined
  3. (C)1, 2
  4. (D)1, not defined
Show answer & solution
Answer: (A) 2, 2
  1. The highest order derivative is , so the order is 2.
  2. The equation is a polynomial in the derivatives and appears with highest power 2, so the degree is 2.
Q131 markMCQIntegrals

Let , . Then, f(x) is :

  1. (A)
  2. (B)
  3. (C)
  4. (D)
Show answer & solution
Answer: (B)
  1. .
  2. , so .
  3. .
Also asked in: 2025 65/6/1, 2025 65/6/2
Q141 markMCQLinear Programming

In a Linear Programming Problem (LPP), the objective function is to be maximised under the following constraints :
, ,
Study the graph and select the correct option.
(Note : The figure is not to scale)
The solution of the given LPP :

Diagram for CBSE 2025 Class 12 Maths question 14
  1. (A)lies in the shaded unbounded region.
  2. (B)lies in AOB.
  3. (C)does not exist.
  4. (D)lies in the combined region of AOB and unbounded shaded region.
Show answer & solution
Answer: (C) does not exist.
  1. means .
  2. No point can satisfy both and .
  3. The two shaded regions have no common part, so there is no feasible region.
  4. Hence the LPP has no solution.
Also asked in: 2025 65/6/1, 2025 65/6/2

The area of the region bounded by the curve between and is :

  1. (A) sq units
  2. (B) sq units
  3. (C)3 sq units
  4. (D) sq units
Show answer & solution
Answer: (D) sq units
  1. The parabola is symmetric about the x-axis; the region between and lies on both sides of it.
  2. Area sq units.
Also asked in: 2025 65/6/1, 2025 65/6/2
Q161 markMCQIntegrals

is equal to :

  1. (A)
  2. (B)
  3. (C)
  4. (D)
Show answer & solution
Answer: (C)
  1. .
  2. With , , so the integrand is .
  3. .
Also asked in: 2025 65/6/1, 2025 65/6/2
Q171 markMCQVector Algebra

Let and . Then, the range of is :

  1. (A)
  2. (B)
  3. (C)
  4. (D)
Show answer & solution
Answer: (D)
  1. .
  2. For , , so the true range of is .
  3. No option gives ; option (D) is the range of , which is what the question intends.
Also asked in: 2025 65/6/1, 2025 65/6/2
Q181 markMCQProbability

A meeting will be held only if all three members A, B and C are present. The probability that member A does not turn up is 0.10, member B does not turn up is 0.20 and member C does not turn up is 0.05. The probability of the meeting being cancelled is :

  1. (A)0.35
  2. (B)0.316
  3. (C)0.001
  4. (D)0.65
Show answer & solution
Answer: (B) 0.316
  1. P(A present) , P(B present) , P(C present) .
  2. Assuming independence, P(meeting held) .
  3. P(meeting cancelled) .
Q191 markAssertion–ReasonVector Algebra

Assertion (A) : If and , then .
Reason (R) : and and .

  1. (A)Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).
  2. (B)Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).
  3. (C)Assertion (A) is true, but Reason (R) is false.
  4. (D)Assertion (A) is false, but Reason (R) is true.
Show answer & solution
Answer: (A) Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).
  1. Reason is true: these are the standard results.
  2. Using them: .
  3. So , , . Assertion is true.
  4. The Reason is exactly what gives the Assertion, so the answer is (A).
Also asked in: 2025 65/6/1, 2025 65/6/2
Q201 markAssertion–ReasonRelations and Functions

Assertion (A) : Let and . Then where domain of is R.
Reason (R) : .

  1. (A)Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).
  2. (B)Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).
  3. (C)Assertion (A) is true, but Reason (R) is false.
  4. (D)Assertion (A) is false, but Reason (R) is true.
Show answer & solution
Answer: (D) Assertion (A) is false, but Reason (R) is true.
  1. Reason is true: is defined only where both f and g are defined.
  2. Dom(f) = R and Dom(g) = .
  3. So Dom, not R.
  4. Assertion is false, Reason is true: answer (D).
Also asked in: 2025 65/6/1, 2025 65/6/2
Q212 marksVery Short AnswerVector Algebra

If and are position vectors of point A and point B respectively, find the position vector of point C on BA produced such that BC = 3BA.

Show answer & solution
Answer:
  1. C lies on BA produced beyond A, so has the same direction as .
  2. , so .
  3. .
Also asked in: 2025 65/6/1, 2025 65/6/2
OR
Q21 (OR) (OR)2 marksVery Short AnswerThree Dimensional Geometry

Vector is inclined at equal angles to the three axes x, y and z. If magnitude of is units, then find .

Show answer & solution
Answer: , i.e. (or its negative)
  1. Let the direction cosines be .
  2. gives , so .
  3. .
  4. .
Also asked in: 2025 65/6/1, 2025 65/6/2
Q222 marksVery Short AnswerInverse Trigonometric Functions

Find the domain of .

Show answer & solution
Answer:
  1. is defined for .
  2. So , i.e. .
  3. always holds, and gives .
  4. Domain .
Also asked in: 2025 65/6/1, 2025 65/6/2
Q232 marksVery Short AnswerApplication of Derivatives

Find the interval in which is always increasing, .

Show answer & solution
Answer: (the end points may be included)
  1. .
  2. when , i.e. or .
  3. for and .
  4. So f is increasing in (also on and ).
Q242 marksVery Short AnswerContinuity and Differentiability

Differentiate with respect to for .

Show answer & solution
Answer:
  1. Let and . Then .
  2. .
  3. (Check via x: and , giving the same ratio.)
Also asked in: 2025 65/6/1, 2025 65/6/2
OR
Q24 (OR) (OR)2 marksVery Short AnswerContinuity and Differentiability

If , then find .

Show answer & solution
Answer:
  1. Taking logs: .
  2. Differentiating: .
  3. .
  4. .
Also asked in: 2025 65/6/1, 2025 65/6/2
Q252 marksVery Short AnswerThree Dimensional Geometry

Find the angle at which the given lines are inclined to each other :

Show answer & solution
Answer:
  1. Direction ratios: : ; : .
  2. .
  3. .
Q263 marksShort AnswerMatrices

Find the value of x, if .

Show answer & solution
Answer: or
  1. .
  2. .
  3. gives .
  4. or .
Q273 marksShort AnswerThree Dimensional Geometry

Find the distance of the point P(2, 4, ) from the line .

Show answer & solution
Answer: 7 units
  1. Any point on the line: .
  2. .
  3. For the foot of the perpendicular, : , so .
  4. Foot .
  5. units.
Also asked in: 2025 65/6/1, 2025 65/6/2
OR
Q27 (OR) (OR)3 marksShort AnswerThree Dimensional Geometry

Let the position vectors of the points A, B and C be , and respectively. Find the vector and cartesian equations of the line passing through A and parallel to line BC.

Show answer & solution
Answer: ;
  1. Direction of BC: .
  2. Vector equation: .
  3. Cartesian equation: (i.e. , ).
Also asked in: 2025 65/6/1, 2025 65/6/2
Q283 marksShort AnswerLinear Programming

Consider the Linear Programming Problem, where the objective function needs to be minimized subject to constraints


.
Draw a neat graph of the feasible region and find the minimum value of Z.

Show answer & solution
Answer: Minimum Z = 800 at (800, 0).
  1. Draw through , and through , .
  2. The feasible region lies on the side away from the origin of both lines, in the first quadrant; it is unbounded.
  3. They meet where and , giving , .
  4. Corner points: , , .
  5. Z values: , , .
  6. Smallest is 800. Check the half-plane : with it needs , so it has no point in common with the region.
  7. Minimum Z = 800 at .
Also asked in: 2025 65/6/1, 2025 65/6/2
Q293 marksShort AnswerRelations and Functions

A student wants to pair up natural numbers in such a way that they satisfy the equation , . Find the domain and range of the relation. Check if the relation thus formed is reflexive, symmetric and transitive. Hence, state whether it is an equivalence relation or not.

Show answer & solution
Answer: Domain , Range ; not reflexive, not symmetric, not transitive; not an equivalence relation.
  1. , so gives .
  2. .
  3. Domain ; Range = odd numbers from 1 to 39.
  4. Not reflexive: since .
  5. Not symmetric: but since .
  6. Not transitive: and , but since .
  7. So R is not an equivalence relation.
Also asked in: 2025 65/6/1, 2025 65/6/2
OR
Q29 (OR) (OR)3 marksShort AnswerRelations and Functions

Show that the function , where N is a set of natural numbers, given by is a bijection.

Show answer & solution
Answer: Proved.
  1. One-one: let .
  2. If are both even: , so . If both odd: , so .
  3. If is odd and is even: is even and is odd, so they cannot be equal.
  4. Hence f is one-one.
  5. Onto: let . If m is odd, is even and . If m is even, is odd and .
  6. So every m has a pre-image; f is onto.
  7. Hence f is a bijection.
Also asked in: 2025 65/6/1, 2025 65/6/2
Q303 marksShort AnswerContinuity and Differentiability

Differentiate w.r.t. x, if .

Show answer & solution
Answer:
  1. Put ; for , .
  2. , with .
  3. So .
  4. .
Also asked in: 2025 65/6/1, 2025 65/6/2
OR
Q30 (OR) (OR)3 marksShort AnswerContinuity and Differentiability

Differentiate with respect to x, when .

Show answer & solution
Answer:
  1. Put ; for , .
  2. , with .
  3. So .
  4. .
Also asked in: 2025 65/6/1, 2025 65/6/2
Q313 marksShort AnswerProbability

Bag I contains 4 white and 5 black balls. Bag II contains 6 white and 7 black balls. A ball drawn randomly by from bag I is transferred to bag II and then a ball is drawn randomly from bag II. Find the probability that the ball drawn is white.

Show answer & solution
Answer:
  1. Let : white ball transferred, : black ball transferred; , .
  2. If white is transferred, bag II has 7 white, 7 black: .
  3. If black is transferred, bag II has 6 white, 8 black: .
  4. .
Q325 marksLong AnswerDifferential Equations

Solve the differential equation : .

Show answer & solution
Answer:
  1. , a homogeneous equation.
  2. Put , so .
  3. , so .
  4. ; integrating, .
  5. Put : , i.e. .
Also asked in: 2025 65/6/1, 2025 65/6/2
OR
Q32 (OR) (OR)5 marksLong AnswerDifferential Equations

Solve the differential equation subject to initial condition .

Show answer & solution
Answer:
  1. Divide by : , a linear equation.
  2. I.F. .
  3. .
  4. gives .
  5. .
Also asked in: 2025 65/6/1, 2025 65/6/2
Q335 marksLong AnswerApplication of Integrals

Using integration, find the area of the ellipse bounded between the lines to .

Show answer & solution
Answer: sq units
  1. Upper half: . By symmetry about both axes,
  2. Area .
  3. .
  4. .
  5. Area .
  6. Area sq units.
Q345 marksLong AnswerIntegrals

Find :

Show answer & solution
Answer:
  1. Write .
  2. So .
  3. : , .
  4. : , .
  5. Coefficient of : , so .
  6. Integral .
  7. .
Also asked in: 2025 65/6/1, 2025 65/6/2
OR
Q34 (OR) (OR)5 marksLong AnswerIntegrals

Evaluate :

Show answer & solution
Answer:
  1. Let .
  2. Using : .
  3. Adding: .
  4. , so .
  5. .
  6. .
  7. So and .
Also asked in: 2025 65/6/1, 2025 65/6/2
Q355 marksLong AnswerThree Dimensional Geometry

Show that the line passing through the points A (0, , ) and B (4, 5, 1) intersects the line joining points C (3, 9, 4) and D (, 4, 4).

Show answer & solution
Answer: Proved. The lines intersect at (10, 14, 4).
  1. Line AB: , general point .
  2. Line CD: direction , general point .
  3. Equate z: , so .
  4. Equate x: , so .
  5. Check y: and . Equal.
  6. All three coordinates agree, so the lines intersect, at .
Q364 marksCase StudyApplication of Derivatives

A ladder of fixed length ‘h’ is to be placed along the wall such that it is free to move along the height of the wall.
Based upon the above information, answer the following questions :
(i) Express the distance (y) between the wall and foot of the ladder in terms of ‘h’ and height (x) on the wall at a certain instant. Also, write an expression in terms of h and x for the area (A) of the right triangle, as seen from the side by an observer. (1)
(ii) Find the derivative of the area (A) with respect to the height on the wall (x), and find its critical point. (1)
(iii) (a) Show that the area (A) of the right triangle is maximum at the critical point. (2)
OR
(iii) (b) If the foot of the ladder whose length is 5 m, is being pulled towards the wall such that the rate of decrease of distance (y) is 2 m/s, then at what rate is the height on the wall (x) increasing, when the foot of the ladder is 3 m away from the wall ? (2)

Show answer & solution
Answer: (i) , (ii) , critical point (iii) (a) Proved. OR (iii) (b) m/s
  1. (i) By Pythagoras, , so .
  2. .
  3. (ii) .
  4. gives (x > 0).
  5. (iii) (a) For , so ; for , .
  6. changes from positive to negative at , so A is maximum there.
  7. (iii) (b) ; when , .
  8. Differentiating: , with .
  9. , so m/s.
Also asked in: 2025 65/6/1, 2025 65/6/2
Q374 marksCase StudyProbability

A shop selling electronic items sells smartphones of only three reputed companies A, B and C because chances of their manufacturing a defective smartphone are only 5%, 4% and 2% respectively. In his inventory he has 25% smartphones from company A, 35% smartphones from company B and 40% smartphones from company C.
A person buys a smartphone from this shop.
(i) Find the probability that it was defective. (2)
(ii) What is the probability that this defective smartphone was manufactured by company B ? (2)

Show answer & solution
Answer: (i) 0.0345 (ii)
  1. Let be: phone from A, B, C; D: phone is defective.
  2. , , ; , , .
  3. (i) .
  4. (ii) By Bayes' theorem, .
Also asked in: 2025 65/6/1, 2025 65/6/2
Q384 marksCase StudyDeterminants

Three students, Neha, Rani and Sam go to a market to purchase stationery items. Neha buys 4 pens, 3 notepads and 2 erasers and pays ₹ 60. Rani buys 2 pens, 4 notepads and 6 erasers for ₹ 90. Sam pays ₹ 70 for 6 pens, 2 notepads and 3 erasers.
Based upon the above information, answer the following questions :
(i) Form the equations required to solve the problem of finding the price of each item, and express it in the matrix form AX = B. (1)
(ii) Find |A| and confirm if it is possible to find . (1)
(iii) (a) Find , if possible, and write the formula to find X. (2)
OR
(iii) (b) Find , where I is an identity matrix. (2)

Show answer & solution
Answer: (i) , , ; (ii) , so exists (iii) (a) , (pen ₹ 5, notepad ₹ 8, eraser ₹ 8) OR (iii) (b)
  1. (i) Let the prices of a pen, a notepad and an eraser be ₹ x, ₹ y, ₹ z.
  2. , , .
  3. , , .
  4. (ii) , so A is non-singular and exists.
  5. (iii) (a) Cofactors: ; ; .
  6. , .
  7. ; this gives , , .
  8. (iii) (b) .
  9. .
Also asked in: 2025 65/6/1, 2025 65/6/2
← 2025 65/6/2 2025 65/7/1 →
Practise smarter: chapter-wise revision, formula sheets and step-by-step NCERT solutions on MonoMath CBSE →